This invention relates to liquid pick-up appliances for use in surface cleaning or drying operations wherein liquid is picked-up for example from a floor surface (afforded by a floor or floor covering) or other surface such as afforded by a wall or window by a suction head so as to be entrained in air flow from such head to an air/liquid separator in which entrained liquid is separated from the air flow and collected in a container.
Such an appliance may be designed and used for drying floor surfaces or picking up spillages, or it may also incorporate a reservoir for a cleaning liquid (which may be water or a suitable cleaning solution) and means for delivering such liquid to a cleaning head, which may be incorporated in, or separate from, the suction head, so that the appliance is capable of carrying out, simultaneously or sequentially, floor cleaning and floor drying operations or similar operations on other surfaces.
Various types of air/liquid separator have been proposed to enable the liquid to be separated from the air flow and delivered to a collection container. For example British Patent specification 1121225 shows a simple centrifugal separator in which the air flow enters an annular chamber tangentially, the lower side of the chamber being connected to the upper end of a collection container. Our British Patent specification 1601456 shows a separator in which the air flow is radially directed into a radially narrow annular space between the outer wall of a reservoir container and the outer wall of a collection chamber within which the reservoir container is nested, the latter having a central suction duct extending through it, and which at its lower end is formed as a downwardly widening cone with vertical vanes to prevent circular air flow.
In other examples, labyrinthine separators are employed, as shown in U.S. Pat. No. 2,986,764. In the case of relatively small hand-held devices which in use may be subjected to quite vigourous motion, elaborate arrangements are often employed within the collection container to prevent entrained droplets from being drawn out of the container, as for example in EP 0170720.
In still other cases a widening inlet tube delivers the air/liquid stream onto baffle arranged across the mouth of the tube, as for example, in German Patent specification 3540956 or U.S. Pat. No. 1,328,339.
In such prior arrangements, the air outlet from the collection chamber is located at a position remote from the air/liquid inlet.